<body>
    <div id="box1" style="height: 100px; width: 100px; background-color: lightblue"></div>
    <button id="pause-btn">pause</button>
    <button id="resume-btn">resume</button>
    <button id="reset-btn">reset</button>
    <button id="start-btn">start</button>
    <script type="module" src="./animation-demo.js"></script>
</body>
